A study of lightning flash initiation prior to the first initial breakdown pulse

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378289%3A_____%2F19%3A00495325" target="_blank" >RIV/68378289:_____/19:00495325 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11320/19:10407437

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.atmosres.2018.10.013" target="_blank" >http://dx.doi.org/10.1016/j.atmosres.2018.10.013</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.atmosres.2018.10.013" target="_blank" >10.1016/j.atmosres.2018.10.013</a>

Jazyk výsledku

angličtina

Název v původním jazyce

A study of lightning flash initiation prior to the first initial breakdown pulse

Popis výsledku v původním jazyce

This study examines the initiation of two intracloud (IC) and two cloud-to-ground (CG) lightning flashes using electric field change (FA) sensors and VHF (LogRF) sensors located at seven sites near Oxford, Mississippi, USA. For each flash the initiating event caused a pulse in the LogRF data and started an Initial E-Change (IEC) in the FA data. The initiating LogRF pulses had powers <1 W and durations of ~1 μs. Numerous LogRF pulses occurred during each IEC: these pulses had durations ≤3 μs. Fewer FA pulses occurred during each IEC: these pulses had durations of ≤7 μs. During each IEC, a few of the LogRF pulses were coincident with a FA pulse, and most such pairs of pulses enhanced the IEC: no IEC enhancing events occurred without such a coincident pair. Each flash had 1 or 2 IEC enhancing events soon after the initiating event and 1 or 2 enhancing events shortly before the first classic initial breakdown (IB) pulse occurred. The point dipole moments and durations of IECs of the two IC flashes were (520C m, 620 μs) and (770C m, 1790 μs) and for the two CG flashes were (9C m, 124 μs) and (36C m, 130 μs). We speculate that the LogRF events were positive corona streamers, that enhancing events occurred when a new streamer extended a previous streamer path, and that this process during the flash initiation developed a nascent channel needed for the negative breakdown of the IB pulses.

Název v anglickém jazyce

A study of lightning flash initiation prior to the first initial breakdown pulse

Popis výsledku anglicky

This study examines the initiation of two intracloud (IC) and two cloud-to-ground (CG) lightning flashes using electric field change (FA) sensors and VHF (LogRF) sensors located at seven sites near Oxford, Mississippi, USA. For each flash the initiating event caused a pulse in the LogRF data and started an Initial E-Change (IEC) in the FA data. The initiating LogRF pulses had powers <1 W and durations of ~1 μs. Numerous LogRF pulses occurred during each IEC: these pulses had durations ≤3 μs. Fewer FA pulses occurred during each IEC: these pulses had durations of ≤7 μs. During each IEC, a few of the LogRF pulses were coincident with a FA pulse, and most such pairs of pulses enhanced the IEC: no IEC enhancing events occurred without such a coincident pair. Each flash had 1 or 2 IEC enhancing events soon after the initiating event and 1 or 2 enhancing events shortly before the first classic initial breakdown (IB) pulse occurred. The point dipole moments and durations of IECs of the two IC flashes were (520C m, 620 μs) and (770C m, 1790 μs) and for the two CG flashes were (9C m, 124 μs) and (36C m, 130 μs). We speculate that the LogRF events were positive corona streamers, that enhancing events occurred when a new streamer extended a previous streamer path, and that this process during the flash initiation developed a nascent channel needed for the negative breakdown of the IB pulses.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Atmospheric Research

ISSN

0169-8095

e-ISSN

—

Svazek periodika

217

Číslo periodika v rámci svazku

1 March

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

14

Strana od-do

10-23

Kód UT WoS článku

000452931100002

EID výsledku v databázi Scopus

2-s2.0-85055630098